KR20060133339A - An apparatus for dispensing a sealant, method of manufacturing liquid crystal display device using the same, and liquid crystal display manufactured by the method - Google Patents

Abstract

A SEALANT dispensing apparatus, a method for manufacturing an LCD using the same, and an LCD manufactured by the method are provided to minimize pattern deformation of a main SEALANT without requiring a further process time by further forming an auxiliary SEALANT encompassing an outer edge of a main SEALANT, and using a SEALANT dispensing apparatus that can simultaneously form the main SEALANT and the auxiliary SEALANT. A syringe(100) receives a sealant. A main nozzle(120) and an auxiliary nozzle(130) are connected to the syringe, and discharge the sealant received in the syringe to the outside. The auxiliary nozzle can rotate around the main nozzle. A distance between the main nozzle and the auxiliary nozzle is controllable. A rotary shaft and a connection bar(140) connecting the rotary shaft and the nozzle are further supplied.

Description

Sealant dispensing apparatus, a method of manufacturing a liquid crystal display device using the same, and a liquid crystal display device manufactured by the same.An Apparatus for dispensing a sealant, method of manufacturing Liquid Crystal Display Device using the same, and Liquid Crystal Display manufactured by the method}

1A to 1C are perspective views illustrating a manufacturing process of a liquid crystal display device by a conventional liquid crystal dropping method.

2A to 2C are process perspective views illustrating a manufacturing process of a liquid crystal display device according to an exemplary embodiment of the present invention.

3A to 3C are process perspective views illustrating a manufacturing process of a liquid crystal display device according to another exemplary embodiment of the present invention.

4 is a schematic cross-sectional view of a seal material dispensing apparatus for manufacturing a liquid crystal display device according to an exemplary embodiment of the present invention.

5A is a perspective view of a liquid crystal display according to an exemplary embodiment before bonding, and FIG. 5B is a cross-sectional view after bonding.

<Explanation of symbols for the main parts of the drawings>

10: lower substrate 30: upper substrate

50: liquid crystal 70: main seal material

80: auxiliary seal material 100: syringe

       110: rotation axis 120: main nozzle

       130: auxiliary nozzle 140: connecting bar

       150: piping

The present invention relates to a liquid crystal display (LCD), and more particularly, to a sealant of a liquid crystal display device by a liquid crystal dropping method.

Ultra-thin flat panel displays with a display screen thickness of only a few centimeters (cm). Among them, liquid crystal displays have low operating voltages, which consume less power and can be used as portable devices. Applications range from monitors to spacecraft to aircraft.

Such a liquid crystal display device generally includes a lower substrate on which a thin film transistor and a pixel electrode are formed, an upper substrate formed to face the lower substrate, and a light blocking film, a color filter layer, and a common electrode formed thereon; The liquid crystal layer is formed between the two substrates. An electric field is formed between the two substrates by the pixel electrode and the common electrode to drive the liquid crystal layer, and the light transmittance is adjusted through the driven liquid crystal layer. Will be displayed.

In the liquid crystal display device having such a structure, a vacuum injection method using a capillary phenomenon and a pressure difference is conventionally used as a method of forming a liquid crystal layer between the lower substrate and the upper substrate. The vacuum injection method is as follows.

First, a lower substrate and an upper substrate are manufactured.

And the sealing material which has an injection hole is formed on any one of the said board | substrate in order to adhere | attach the said both board | substrates.

After the two substrates are bonded together, the seal member is cured to form a bonded substrate.

The bonded substrate is placed in a vacuum chamber, and the inside of the bonded substrate is kept in a vacuum state and then immersed in the liquid crystal. As such, when the inside of the bonded substrate becomes a vacuum, the liquid crystal is sucked up through the injection hole of the bonded substrate by a capillary phenomenon, thereby forming a liquid crystal layer inside the bonded substrate.

However, in this vacuum injection method, as the display screen becomes larger, the liquid crystal injection time takes a long time, resulting in a problem of low productivity.

Therefore, in order to solve the above problems, a new method called a liquid crystal dropping method has been proposed. Hereinafter, a method of manufacturing a liquid crystal display device by a conventional liquid crystal dropping method will be described with reference to the accompanying drawings.

1A to 1C are perspective views illustrating a manufacturing process of a liquid crystal display device by a conventional liquid crystal dropping method.

First, as shown in FIG. 1A, the lower substrate 1 and the upper substrate 3 are prepared.

As shown in FIG. 1B, a sealing material 7 without an injection hole is formed on the lower substrate 1, and the liquid crystal 5 is dropped to form a liquid crystal layer.

As shown in FIG. 1C, after the lower substrate 1 and the upper substrate 3 are bonded together, the seal member 7 is cured to manufacture a liquid crystal display device.

As described above, in the case of the liquid crystal dropping method, since the liquid crystal is directly dropped on the substrate, the time required for injecting the liquid crystal is not required as in the liquid crystal injection method, and the manufacturing process is very shortened.

However, in such a liquid crystal dropping method, a problem arises in that the seal member 7 without the injection hole is deformed by external pressure during the bonding process.

That is, in the case of the conventional vacuum injection method, since the seal material is formed in a pattern having an injection hole, the injection hole is formed inside and outside by the injection hole during the bonding process so that it is less affected by external pressure, but in the case of the liquid crystal drop method. Since the seal material is formed in a pattern without an injection hole, there is a problem in that the seal material pattern is deformed when an external pressure is applied during the bonding process.

The present invention has been made to solve the above problems, and an object of the present invention is to provide a method for manufacturing a liquid crystal display device in which the pattern of the sealing material is not deformed during the bonding process in manufacturing the liquid crystal display device by the liquid crystal dropping method. .

Another object of the present invention is to provide a sealing material dispensing apparatus for forming the sealing material of the liquid crystal display device.

Another object of the present invention is to provide a liquid crystal display device manufactured using the seal material dispensing apparatus.

In order to achieve the above object, the present invention comprises the steps of preparing a lower substrate and an upper substrate; Dropping liquid crystal onto any one of the above substrates; Forming a main seal material without an injection hole on one of the substrates; Forming an auxiliary seal material on one of the substrates to surround the main seal material; And bonding the substrates together, wherein the forming of the main sealing material and the forming of the auxiliary sealing material are performed at the same time. .

That is, the present invention is to further form the auxiliary seal material to surround the main seal material without the injection hole, so as to minimize the pattern deformation of the main seal material even if the external pressure acts during the bonding process. Here, the main seal material is to seal the liquid crystal, which is the original purpose of the seal material, and serves to bond the lower substrate and the upper substrate, and the auxiliary seal material is to protect the main seal material, and the auxiliary seal material is after the bonding process. It can be removed in the cell cutting process.

At this time, the present invention is not formed by the main seal material and the auxiliary seal material in a separate process, but by forming a simultaneous process so that the additional processing time is not required due to the formation of the auxiliary seal material.

Here, when the main seal material and the auxiliary seal material are formed, the seal material may be formed to have a gap enough to be connected by compression during the bonding process without forming the seal material in a completely closed type.

The process of simultaneously forming the main seal material and the auxiliary seal material is preferably performed using a dispensing apparatus having a main nozzle and an auxiliary nozzle.

The present invention also provides a sealing material dispensing apparatus capable of simultaneously forming the main sealing material and the auxiliary sealing material. That is, the present invention is a syringe containing a seal material; And a main nozzle and an auxiliary nozzle connected to the syringe to discharge the seal material accommodated in the syringe to the outside, wherein the auxiliary nozzle can rotate around the main nozzle. Provided is a sealing material dispensing device for device manufacturing.

That is, the present invention is to connect the main nozzle and the auxiliary nozzle to a single syringe to form the main seal material and the auxiliary seal material at the same time, wherein the auxiliary nozzle is configured to rotate around the main nozzle to the outer side of the main seal material It is designed to smoothly form the auxiliary seal material to be formed.

It is preferable to form the distance between the main nozzle and the auxiliary nozzle so that the distance between the main seal material and the auxiliary seal material can be properly adjusted.

In addition, the seal material dispensing apparatus preferably further includes a pattern check unit for checking whether the seal material is formed disconnected or the line width.

The present invention also provides a liquid crystal display device manufactured using the dispensing device. That is, the present invention is a lower substrate and an upper substrate; A main seal material formed without an injection hole between the two substrates; An auxiliary seal material formed to surround an outer portion of the main seal material; And a liquid crystal layer formed inside the main seal material, wherein the main seal material is formed in a rectangular structure, and the auxiliary seal material is formed in a rectangular structure having four corners having a round shape. to provide.

Hereinafter, exemplary embodiments of the present invention will be described with reference to the accompanying drawings.

1. Manufacturing method of liquid crystal display device

2A to 2C are process perspective views illustrating a manufacturing process of a liquid crystal display device according to an exemplary embodiment of the present invention.

First, as shown in FIG. 2A, the lower substrate 10 and the upper substrate 30 are prepared.

Although not shown in the drawing, a plurality of gate wirings and data wirings are formed on the lower substrate 10 to cross each other in a vertical direction, and define a gate electrode, a semiconductor layer, a source electrode, at the intersection of the gate wiring and the data wiring. And a thin film transistor including a drain electrode, and a pixel electrode connected to the thin film transistor is formed in the pixel region.

In addition, a light shielding film is formed on the upper substrate 30 to block light leakage from the gate wiring, data wiring, and thin film transistor forming regions, and a color filter layer of red, green, and blue is formed on the light blocking film. A common electrode is formed on the color filter layer.

In the case of a so-called IPS (In Plane Switching) mode liquid crystal display device, the common electrode is not formed on the upper substrate but on the lower substrate. More specifically, the common electrode is formed parallel to the pixel electrode to induce a transverse electric field between the pixel electrode and the common electrode, and an overcoat layer is formed on the common electrode dash on the color filter of the upper substrate to planarize the substrate. Promote.

In addition, an alignment layer for initial alignment of liquid crystals may be formed on at least one of the lower substrate 10 and the upper substrate 30.

In this case, the alignment layer may be formed by rubbing alignment treatment of a polyamide or polyimide compound, PVA (polyvinylalcohol), polyamic acid, or the like, or PVCN (polyvinylcinnamate) or PSCN (polyvinylcinnamate). Photoreactive materials such as polysiloxanecinnamate) or CelCN (cellulosecinnamate) -based compounds may be formed by photoalignment treatment.

Thereafter, as shown in FIG. 2B, the liquid crystal 50 is dropped on the lower substrate 10, and the main seal material 70 and the auxiliary seal material 80 are simultaneously formed on the upper substrate 30.

Although only four unit cells are shown in the drawing, the number of unit cells may be variously changed in consideration of the size of the substrate.

In addition, although the size of each unit cell may be all the same, unit cells of different sizes may be formed.

The liquid crystal 50 is preferably added dropwise to the central portion of the unit cell. The reason is that the liquid crystal 50 may be main and auxiliary before the main and auxiliary seal materials 70 and 80 are cured during the bonding process. This is because the liquid crystal 50 is contaminated when it meets the auxiliary seal materials 70 and 80. As such, the liquid crystal 50 dropped in the central portion is gradually spread until the main and auxiliary seal materials 70 and 80 are cured, and are distributed at the same density throughout the substrate.

The main and auxiliary seal materials 70 and 80 are formed in a closed pattern without an injection hole, and may be formed using a screen printing method or a dispenser method. However, the screen printing method may damage the elements formed on the substrate because the screen is in contact with the substrate, and when the substrate is large, the loss amount of the sealing material is increased, which is more economical, and therefore, it is more preferable to use the dispenser method.

In the case of forming the main and auxiliary seal materials 70 and 80 using a dispenser method, a main nozzle for forming the main seal material 70 and an auxiliary nozzle for forming the auxiliary seal material 80 are provided. It is preferable to perform using one dispensing apparatus, the specific structure of which will be described later.

2B illustrates a state in which the main seal material 70 and the auxiliary seal material 80 are simultaneously formed by using a dispensing device having a main nozzle and an auxiliary nozzle, and when the dispensing device is used, the main seal material 70 is formed. Seal material 70 is formed in a rectangular structure and the auxiliary seal material 80 is formed in a rectangular structure having four corners in a round shape. The specific formation method will be described later.

However, when the main and auxiliary seal materials 70 and 80 are formed by screen printing, the auxiliary seal material 80 may also be formed in the same rectangular structure as the main seal material 70.

The line widths of the main seal material 70 and the auxiliary seal material 80 may be the same, but may be different from each other. Since the auxiliary seal material 80 may be removed later in the cell cutting process, if the line width is too large, the cell cutting process may be difficult. Therefore, it is advantageous for the cell cutting process to form the line width of the auxiliary seal material 80 smaller than the line width of the main seal material 70.

As the material of the main and auxiliary seal materials 70 and 80, it is preferable to use a UV-curable seal material. As the UV-curable seal material, a polymer having an acrylic group bonded to both ends thereof may be mixed with an initiator, or a polymer having an acrylic group bonded to the other end thereof with an epoxy group may be mixed with the initiator.

Meanwhile, although the liquid crystal 50 is dropped on the lower substrate 10 and the seal members 70 and 80 are formed on the upper substrate 30, the present invention is not limited thereto, and the upper substrate 30 is not limited thereto. The liquid crystal 50 may be dropped on the lower substrate 10, and the seal members 70 and 80 may be formed on the lower substrate 10. In addition, the liquid crystal 50 and the seal members 70 and 80 may be formed on the same substrate. However, when the liquid crystal 50 and the seal material 70 and 80 are formed on the same substrate, an imbalance occurs between the process of the liquid crystal and the seal material on which the substrate is formed and the substrate that does not form the process, and the process takes a lot of time. Since the seal material is formed on the same substrate, even if contaminants are formed on the seal material before the bonding process, the substrate cannot be cleaned, and therefore, the liquid crystal and the seal material are preferably formed on different substrates.

In addition, although not shown in the drawings, a spacer for maintaining a cell gap may be formed on any one of the substrates 10 and 30, preferably the upper substrate 30.

The spacer may be a ball spacer or a column spacer. In the case of the ball spacer, when applied to a large area, there is a disadvantage in that the cell gap is uneven. Therefore, it is preferable to use a column spacer for a large area substrate.

It is preferable to use photosensitive organic resin as a material of the column spacer, and the position at which the column spacer is formed is preferably a position corresponding to the position at which the light shielding film is formed.

Thereafter, as shown in Fig. 2C, the substrates 10 and 30 are bonded together.

In the bonding process, the lower substrate 10 on which the liquid crystal is dropped is placed on the lower surface of the two substrates 10 and 30, and a layer forming surface of the remaining upper substrate 30 faces the lower substrate 10. Rotate 180 degrees so as to be located on the upper surface to be bonded.

Thereafter, although not illustrated, the sealing material 70 and 80 may further include a curing process after the bonding process. The seal material (70, 80) curing process is determined according to the material of the seal material, in the case of the above-mentioned UV-curable seal material, the seal material curing process may be performed by a UV irradiation process alone or a combination of UV irradiation process and heating process.

On the other hand, in the case of irradiating UV for curing the seal material, if UV is irradiated to the entire surface of the bonded substrate, it may adversely affect device characteristics such as a thin film transistor formed on the substrate, and an alignment layer formed for initial alignment of liquid crystals. The pretilt angle of may be changed. Therefore, when irradiating UV light for curing the seal material, it is preferable to cover the area other than the area where the seal materials 70 and 80 are formed with a mask.

In addition, although not shown, the method may further include a step of cutting in cell units after the bonding process, and the auxiliary seal material 80 may be removed in the step of cutting in cell units.

3A to 3C are process perspective views illustrating a manufacturing process of a liquid crystal display device according to another exemplary embodiment of the present invention.

In the method of manufacturing the liquid crystal display device according to the present embodiment, a lower substrate 10 and an upper substrate 30 are prepared as shown in FIG. 3A, and a liquid crystal 50 is dropped on the lower substrate 10 as shown in FIG. 3B. A main seal material 70 and an auxiliary seal material 80 are formed on the upper substrate 30 at the same time, and then, as shown in FIG. 3C, the two substrates are bonded together to manufacture a liquid crystal display device. FIG. 3B. The method of manufacturing the liquid crystal display device according to FIG. 2 except that the main seal member 70 and the auxiliary seal member 80 are formed to have an interval enough to be connected by compression during the bonding process in the process of same. Therefore, the same reference numerals are given, and descriptions of the same parts will be omitted.

As can be seen in area “A” of FIG. 3B, the seal members 70 and 80 are completely closed in the process of forming the main seal member 70 and the auxiliary seal member 80 on the upper substrate 30. It can be formed at predetermined intervals without forming. The gap is a space that can be connected by compression during the bonding process. That is, when the two substrates 10 and 30 are pressed in the bonding process of FIG. 3C, the seal members 70 and 80 are stretched by a predetermined distance by pressing, so that the predetermined intervals are connected to each other in the bonding process until they are closed. The seal members 70 and 80 of the mold are to be formed.

2. Seal material dispensing device for liquid crystal display device manufacturing

4 is a schematic cross-sectional view of a seal material dispensing apparatus for manufacturing a liquid crystal display device according to an exemplary embodiment of the present invention.

As can be seen in Figure 4, the dispensing apparatus according to the present invention comprises a syringe 100 and a nozzle unit 101 connected to the syringe. The nozzle unit 101 includes a rotation shaft 110, a main nozzle 120, an auxiliary nozzle 130, a connection bar 140, and a pipe 150.

The syringe 100 accommodates the seal material, and is connected to the main nozzle 120 and the auxiliary nozzle 130 by the pipe 150, respectively. Therefore, the seal material accommodated in the syringe 100 is moved to the main nozzle 120 and the auxiliary nozzle 130 through the pipe 150 to be discharged to the outside. The main nozzle 120 is for forming the main seal material 70, and the auxiliary nozzle 130 is for forming the auxiliary seal material 80.

The rotation shaft 110 is connected to the connection bar 140, and the main nozzle 120 and the auxiliary nozzle 130 are connected to the connection bar 140.

Here, the main nozzle 120 is opposed to the rotating shaft 110 with the connecting bar 140 therebetween, and the auxiliary nozzle 130 is spaced apart from the rotating shaft 110 at a predetermined distance. . Accordingly, when the rotation shaft 110 rotates, the main nozzle 120 rotates in place and the auxiliary nozzle 130 rotates around the main nozzle 120. By this principle, in the above-described Figure 2b, the main seal material 70 is formed in a rectangular structure, the auxiliary seal material 80 is formed in a rectangular structure consisting of four corners round.

In addition, since the auxiliary nozzle 130 is movable through the connection bar 140, the distance between the main nozzle 120 and the auxiliary nozzle 130 is adjusted. Therefore, in FIG. 2B, the distance between the main seal material 70 and the auxiliary seal material 80 is adjusted.

In addition, although not shown, the seal material dispensing apparatus may further include a pattern check unit.

The pattern confirmation unit may be configured as a Charged Coupled Device (CCD) camera.

The pattern check unit is for checking the disconnection or line width of the seal member to be formed, and is preferably located in a path through which the main nozzle 120 and the auxiliary nozzle 130 are moved, and the number thereof is one or two or more. Can be.

3. LCD display device

5A is a perspective view of a liquid crystal display according to an exemplary embodiment before bonding, and FIG. 5B is a cross-sectional view after bonding.

As shown in FIGS. 5A and 5B, the liquid crystal display device according to an exemplary embodiment of the present invention may include a main seal material 70 formed between the lower substrate 10, the upper substrate 30, and the substrates 10 and 30. ) And the auxiliary seal material 80, and the liquid crystal layer 50 formed between the substrates 10 and 30.

The structures of the lower substrate 10 and the upper substrate 30 are the same as described above, and thus will be omitted.

The main seal material 70 and the auxiliary seal material 80 are formed by a dispensing device, the main seal material 70 is formed in a rectangular structure, and the auxiliary seal material 80 is the main seal material 70. ) Four corners are formed in a round structure surrounding the outer part.

The main seal member 70 and the auxiliary seal member 80 may be formed at a predetermined interval as described above before bonding, but are formed in a closed type without an injection hole after bonding.

The main seal material 70 and the auxiliary seal material 80 is preferably made of a UV-curable seal material.

As mentioned above, although the preferred embodiment of the present invention has been described, the present invention is not limited to the above embodiment, and may be modified within the scope obvious to those skilled in the art.

According to the present invention by the above configuration, by further forming an auxiliary seal material to surround the outer main seal material, even if the external pressure acts during the bonding process, the pattern deformation of the main seal material is minimized.

In addition, the present invention can simultaneously form the main seal material and the auxiliary seal material by using a seal material dispensing device configured to connect the main nozzle and the auxiliary nozzle to one syringe, respectively, and configure the auxiliary nozzle to rotate around the main nozzle. As such, the main seal material and the auxiliary seal material are not formed in a separate process but are formed in a simultaneous process, so that additional processing time is not required due to the formation of the auxiliary seal material.

Claims (21)

Preparing a lower substrate and an upper substrate; Dropping liquid crystal onto any one of the above substrates; Forming a main seal material without an injection hole on one of the substrates; Forming an auxiliary seal material on one of the substrates to surround the main seal material; And Including the step of bonding both substrates, In this case, the step of forming the main seal material and the step of forming the auxiliary seal material are performed at the same time characterized in that the manufacturing method of the liquid crystal display device. The method of claim 1, The process of forming the main seal material and the auxiliary seal material, the manufacturing method of the liquid crystal display device, characterized in that formed to have a gap enough to be connected by pressing during the bonding process. The method according to claim 1 or 2, And simultaneously forming the main seal material and the auxiliary seal material by using a dispensing apparatus having a main nozzle and an auxiliary nozzle. The method of claim 3, The main seal material is formed in a rectangular structure, and the auxiliary seal material is a manufacturing method of the liquid crystal display device, characterized in that the four corners are formed in a rectangular structure having a round shape. The method of claim 1, And a line width of the main seal material and a line width of the auxiliary seal material are different from each other. The method according to claim 1 or 2, And a sealing material curing step after the bonding step. The method of claim 6, The seal material curing process is a manufacturing method of the liquid crystal display device, characterized in that consisting of a UV irradiation process. The method of claim 7, wherein The UV irradiation process is a method for manufacturing a liquid crystal display device, characterized in that to cover the area other than the region where the seal material is formed with a mask. The method of claim 6, The seal material curing process is a manufacturing method of the liquid crystal display device, characterized in that consisting of a UV irradiation step and a heating step. The method of claim 9, The UV irradiation process is a method for manufacturing a liquid crystal display device, characterized in that to cover the area other than the region where the seal material is formed with a mask. The method according to claim 1 or 2, And removing the auxiliary sealing material by cutting the cell unit after the bonding step. Syringes for receiving seal materials; And Is connected to each of the syringe is made including a main nozzle and an auxiliary nozzle for discharging the seal material accommodated in the syringe to the outside, Sealing material dispensing apparatus for manufacturing a liquid crystal display device, characterized in that the auxiliary nozzle can rotate around the main nozzle. The method of claim 12, Sealing material dispensing device for a liquid crystal display device, characterized in that the distance between the main nozzle and the auxiliary nozzle is adjustable. The method of claim 12, And the dispensing device further comprises a rotating shaft and a connecting bar connecting the rotating shaft and the nozzle. The method of claim 14, The main nozzle is opposed to the rotation axis with the connecting bar interposed therebetween, and the auxiliary nozzle is formed to be spaced apart from the rotation axis by a predetermined distance so that the auxiliary nozzle rotates around the main nozzle by the rotation of the rotation axis. Seal material dispensing apparatus for manufacturing a liquid crystal display device, characterized in that formed. The method of claim 14, And the auxiliary nozzle is formed to be movable through the connection bar, and thus a distance between the main nozzle and the auxiliary nozzle is controlled. The method of claim 12, Sealing material dispensing apparatus for manufacturing a liquid crystal display device, characterized in that the main nozzle and the auxiliary nozzle are each connected to the syringe by a pipe. The method of claim 12, Seal material dispensing device for manufacturing a liquid crystal display device, characterized in that it further comprises a pattern check unit for confirming the disconnection or line width of the seal material. A lower substrate and an upper substrate; A main seal material formed without an injection hole between the substrates; An auxiliary seal material formed to surround an outer portion of the main seal material; And It includes a liquid crystal layer formed inside the main seal material, The main seal material is formed in a rectangular structure, the auxiliary seal material is a liquid crystal display device, characterized in that formed in a rectangular structure consisting of four corners round. The method of claim 19, The main seal material and the auxiliary seal material is a liquid crystal display device, characterized in that made of a UV-curable seal material mixed with an initiator a polymer having an acrylic group bonded to both ends. The method of claim 19, The main seal material and the auxiliary seal material is a liquid crystal display device, characterized in that made of a UV-curable seal material mixed with an initiator a polymer having an acrylic group bonded to the other end of the epoxy group on the other end.

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